CN108488872B - Low-quality steam heating system applied to wet cooling unit - Google Patents
Low-quality steam heating system applied to wet cooling unit Download PDFInfo
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- CN108488872B CN108488872B CN201810262327.4A CN201810262327A CN108488872B CN 108488872 B CN108488872 B CN 108488872B CN 201810262327 A CN201810262327 A CN 201810262327A CN 108488872 B CN108488872 B CN 108488872B
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- 238000010438 heat treatment Methods 0.000 title claims abstract description 28
- 238000001816 cooling Methods 0.000 title claims abstract description 13
- 238000002955 isolation Methods 0.000 claims description 24
- 238000000605 extraction Methods 0.000 claims description 9
- 238000002156 mixing Methods 0.000 claims description 4
- 239000008400 supply water Substances 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 12
- 238000010276 construction Methods 0.000 abstract description 3
- 239000012530 fluid Substances 0.000 description 12
- 238000002347 injection Methods 0.000 description 10
- 239000007924 injection Substances 0.000 description 10
- 238000005516 engineering process Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000009466 transformation Effects 0.000 description 3
- 238000010248 power generation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D1/00—Steam central heating systems
- F24D1/02—Steam central heating systems operating with live steam
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D1/00—Steam central heating systems
- F24D1/08—Feed-line arrangements, e.g. providing for heat-accumulator tanks, expansion tanks
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Jet Pumps And Other Pumps (AREA)
Abstract
The invention discloses a low-quality steam heating system applied to a wet cooling unit, which comprises a heating network heater, wherein the heating network heater is connected with a medium-pressure cylinder steam exhaust pipeline, and the low-quality steam heating system further comprises: the low-pressure cylinder is connected with the steam exhaust pipeline of the medium-pressure cylinder; a plurality of low pressure heaters connected to the low pressure cylinder; the condenser is connected with the low-pressure cylinder; at least one jet pump, the steam inlet of each jet pump is connected with the steam exhaust pipeline of the medium-pressure cylinder, and the suction port of each jet pump is respectively connected with the pipeline between each low-pressure heater and the low-pressure cylinder; and the heater is respectively connected with the jet orifice of each jet pump, the heat supply network heater and the heat supply network water return pipeline. According to the invention, the low-pressure cylinder is not required to be modified, the construction is relatively simple, steam is extracted by using the low-temperature heaters #7 and #8 with lower quality, and the circulating water of the heat supply network is heated, namely, the heat energy of low-quality steam is fully utilized, the circulating water temperature of the heat supply network is improved, and the heat supply capacity of a unit is improved.
Description
Technical Field
The invention relates to a heating system, in particular to a low-quality steam heating system applied to a wet cooling unit.
Background
In recent years, under the encouragement and promotion of national energy conservation and emission reduction policies, various power generation enterprises reform a heat supply unit in areas with heat supply conditions through various technologies to increase heat supply capacity, thereby meeting urban heat supply requirements in winter, and the development has become a necessary trend.
At present, the heat supply transformation of a unit generally adopts technologies such as punching steam extraction, high back pressure of a steam turbine and the like to improve the water outlet temperature of circulating water of a heat supply network.
The turbine high back pressure technology is to improve the back pressure of the unit by reforming the low pressure cylinder and the rotor or by operating adjustment; the high back pressure heat supply transformation of the air cooling unit is relatively simple, the back pressure can be improved through the operation adjustment of the air cooling island, the wet cooling unit is generally about 4-6KPa due to lower operation back pressure, the working condition in winter is below the rated value, the extraction is difficult, the low pressure cylinder is required to be subjected to complex through flow transformation, the construction amount is large, and the cost is high.
Disclosure of Invention
The invention aims to solve the problems, and thus provides a low-quality steam heating system applied to a wet cooling unit.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
a low quality steam heating system for a wet cooling unit, the low quality steam heating system comprising a heating network heater connected to a medium pressure cylinder steam exhaust pipeline by a pipeline, the low quality steam heating system further comprising:
the low-pressure cylinder is connected with the medium-pressure cylinder steam exhaust pipeline through a pipeline;
the low-pressure heaters comprise a #6 low-pressure heater 310, a #7 low-pressure heater 320 and a #8 low-pressure heater 330 which are sequentially connected in series, and the #8 low-pressure heater 330 is connected with a condenser;
the condenser is connected with the low-pressure cylinder through a pipeline and is also connected with the low-pressure heater in series through a pipeline;
at least one jet pump, the steam inlet of each jet pump is connected with the steam exhaust pipeline of the medium-pressure cylinder through a pipeline, and the suction port of each jet pump is connected with the pipeline between each low-pressure heater and the low-pressure cylinder through a pipeline respectively;
and the heater is respectively connected with the jet orifice of each jet pump, the heat supply network heater and the heat supply network water return pipeline through pipelines.
In a preferred embodiment of the present invention, the plurality of low-pressure heaters includes a #6 low-pressure heater, a #7 low-pressure heater and a #8 low-pressure heater which are sequentially connected in series, and the #8 low-pressure heater is connected with the condenser.
In a preferred embodiment of the invention, the heater is a STEJE heater.
In a preferred embodiment of the invention, a first isolation valve is provided in the conduit between each low pressure heater and the low pressure cylinder.
In a preferred embodiment of the invention, the pipeline connecting the suction port of the jet pump with the pipeline between each low-pressure heater and the low-pressure cylinder is respectively provided with a second isolation valve, the pipeline between the steam inlet of the jet pump and the steam exhaust pipeline of the medium-pressure cylinder is provided with a third isolation valve, and the pipeline between the jet port of the jet pump and the heater is provided with a fourth isolation valve.
In a preferred embodiment of the invention, a fifth isolation valve is arranged on the pipeline between the heat supply network heater and the medium pressure cylinder steam exhaust pipeline.
In a preferred embodiment of the present invention, the injection coefficient of the injection port of the injection pump is:
wherein,
wherein,f 3 for mixing chamber cross-sectional area, m 2 ；f 1 For working nozzle exit area, m 2 ； For the working nozzle loss factor, +.>For the suction chamber loss coefficient Δp p For pressure difference, pa, Δp, between working fluid and injected fluid when entering the pump d In order to increase the pressure of the injected fluid after passing through the injection pump, pa, < >>For the mixed loss factor, < >>Is the diffuser loss coefficient; upsilon (v) p 、υ H 、υ d The specific volumes of the working fluid, the ejected fluid and the mixed fluid of the ejection pump outlet are respectively m 3 /kg。
The beneficial effects of the invention are as follows:
the invention has simple structure, no need of modifying a low-pressure cylinder, relatively simple construction, and heating of the heat supply network circulating water by using the low-temperature heaters #7 and #8 with lower quality to extract steam, namely, the heat energy of low-quality steam is fully utilized, the circulating water temperature of the heat supply network is improved, and the heat supply capacity of a unit is improved.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic structural view of the present invention.
Detailed Description
The invention is further described with reference to the following detailed drawings in order to make the technical means, the creation characteristics, the achievement of the purpose and the effect of the implementation of the invention easy to understand.
Referring to fig. 1, the low-quality steam heating system applied to a wet cooling unit provided by the present invention includes a heating network heater 100, a low pressure cylinder 200, a plurality of low pressure heaters, a condenser 400, at least one jet pump 500 and a heater 600.
The heat supply network heater 100 can be connected with a medium pressure cylinder steam exhaust pipeline through a pipeline, and the heat supply network heater 100 can heat the heat supply network backwater by taking the medium pressure cylinder steam exhaust as a heat source so as to meet the requirement of heat supply network water supply.
Because the quality of the medium pressure cylinder exhaust steam discharged by the medium pressure cylinder exhaust steam pipeline is very high, if the medium pressure cylinder exhaust steam pipeline is only used for heating the heat supply network backwater, waste can be caused.
In addition, the heating cannot be performed even in winter.
The low-pressure cylinder 200, the plurality of low-pressure heaters, the condenser 400, the at least one jet pump 500 and the heater 600 are arranged in the system heating system, so that resources can be saved greatly, and the system heating system is suitable for winter use.
And a low pressure cylinder 200 connected to the medium pressure cylinder exhaust pipe through a pipe.
The low-pressure heaters 300 are sequentially connected in series, specifically including a #6 low-pressure heater 310, a #7 low-pressure heater 320 and a #8 low-pressure heater 330 which are sequentially connected in series, and the low-pressure heaters 300 are respectively connected with the low-pressure cylinder 200 through pipes.
The condenser 400 is connected to the #8 low-pressure heater 330 and the low-pressure cylinder 200 through pipes, respectively, and is used for realizing the step-by-step steam extraction of each low-pressure heater 300.
The specific number of the jet pumps 500 can be determined according to actual requirements, the number in this embodiment is specifically 1, the steam inlet of the jet pump 500 is connected to the steam exhaust pipeline of the medium pressure cylinder through a pipeline, and the suction ports of the jet pump are respectively connected to the pipelines between each low pressure heater 300 and the low pressure cylinder 200 through pipelines.
The jet pump 500 may mix the medium pressure cylinder exhaust steam with the extraction steam of the #7 low pressure heater 320 and the #8 low pressure heater 330 and then deliver the mixed low quality steam to the heater 600.
Taking a 300MW wet cooling unit as an example, the back pressure of the condenser 400 is 4.9KPa, the extraction pressure of the #8 low-pressure heater 330 is 17KPa under the 75% load working condition, and the temperature is 58 ℃; the extraction pressure of the low-pressure heater 320 is 47KPa, and the temperature is 81 ℃; the back pressure of the condenser 400 is low, the exhaust steam is difficult to use, the steam extraction of the #7 low-pressure heater 320 and the #8 low-pressure heater 330 before the steam is exhausted from the low-pressure cylinder 200 is pumped through the jet pump 500, the quality is low, and the heat can be used in a heat supply network system by utilizing the jet pump 500 technology, so that the temperature of circulating water of the heat supply network is increased.
The low-quality steam is utilized for heat supply, the economy is far greater than power generation, the pumping quantity of the low-quality steam for heat supply depends on the performance of the jet pump 500, and in order to realize that the low-quality steam jetted by the jet pump 500 can enable the heater 600 to heat the heat supply network backwater, the injection coefficient of the jet orifice of the jet pump 500 is as follows:
wherein,
wherein,f 3 for mixing chamber cross-sectional area, m 2 ；f 1 For working nozzle exit area, m 2 ； For the working nozzle loss factor, +.>For the suction chamber loss coefficient Δp p For pressure difference, pa, Δp, between working fluid and injected fluid when entering the pump d In order to increase the pressure of the injected fluid after passing through the injection pump, pa, < >>For the mixed loss factor, < >>Is the diffuser loss coefficient; upsilon (v) p 、υ H 、υ d The specific volumes of the working fluid, the ejected fluid and the mixed fluid of the ejection pump outlet are respectively m 3 /kg。
The above injection coefficient is that the heater 600 can heat the return water of the heat supply network and has the best energy-saving effect only by adopting the above injection coefficient after numerous experiments and creative labor activities.
The heater 600, which is specifically a STEJE heater, is connected to the injection port of the injection pump 500, the heat supply network heater 100, and the heat supply network water return pipe, respectively, through pipes.
The heat supply network backwater is transmitted to the heater 600 through a heat supply network backwater pipeline, then the heater 600 heats the low-quality steam input by the jet pump 500, and then the heated heat supply network backwater is transmitted to the heat supply network heater 100, and the heat supply network heater 100 does not work to directly supply water to the heat supply network.
In order to facilitate control of communication between the above-described respective components, first isolation valves 710 are provided on the pipes between the respective low-pressure heaters 300 and the low-pressure cylinder 200, respectively;
the second isolation valves 720 are respectively arranged on the pipelines of the suction ports of the jet pump 500 and the pipeline connection between each low-pressure heater 300 and the low-pressure cylinder 200, the third isolation valve 730 is arranged on the pipeline between the steam inlet of the jet pump 500 and the steam exhaust pipeline of the medium-pressure cylinder, and the fourth isolation valve 740 is arranged on the pipeline between the jet port of the jet pump 500 and the heater 600;
a fifth isolation valve 750 is provided on the pipe between the heating network heater 100 and the medium pressure cylinder exhaust pipe, and a sixth isolation valve 760 is provided on the medium pressure cylinder exhaust pipe.
The following is a specific working procedure of the present application:
closing a first isolation valve 710 on a pipeline between the low-pressure cylinder 200 and the #7 low-pressure heater 320 and the #8 low-pressure heater 330, then opening each second isolation valve 720 between the low-pressure cylinder 200 and the jet pump 500, arranging a third isolation valve 730 on a pipeline between a steam inlet of the jet pump 500 and a steam exhaust pipeline of the medium-pressure cylinder, and an isolation valve 740 between an outlet of the jet pump 500 and the heater 600, then operating the jet pump 500, mixing the steam exhaust of the medium-pressure cylinder and the steam extraction of the #7 low-pressure heater 320 and the #8 low-pressure heater 330, then delivering the mixed low-quality steam to the heater 600, fully utilizing heat energy thereof, heating heat supply network backwater, reducing medium-exhaust steam quantity of the heat supply network heater 100, and improving unit economy.
The foregoing has shown and described the basic principles and main features of the present invention and the advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (2)
1. Be applied to low quality steam heating system of wet cooling unit, low quality steam heating system includes the heat supply network heater, the heat supply network heater passes through the exhaust steam pipeline of piping connection intermediate pressure jar, its characterized in that, low quality steam heating system still includes: a low pressure cylinder, a plurality of low pressure heaters, a condenser, at least one jet pump and a heater,
the low pressure cylinder is connected with a medium pressure cylinder steam exhaust pipeline through a pipeline;
the low-pressure heaters are sequentially connected in series, and each low-pressure heater is connected with the low-pressure cylinder through a pipeline; the low-pressure heaters comprise a #6 low-pressure heater, a #7 low-pressure heater and a #8 low-pressure heater which are sequentially connected in series, and the #8 low-pressure heater is connected with the condenser; a first isolation valve is respectively arranged on the pipeline between each low-pressure heater and each low-pressure cylinder;
the condenser is connected with the low-pressure cylinder through a pipeline, and is also connected with the low-pressure heaters after being connected in series through a pipeline to realize gradual steam extraction of each low-pressure heater;
the steam inlet of each jet pump is connected with a steam exhaust pipeline of the medium pressure cylinder through a pipeline, the suction port of each jet pump is connected with a pipeline between each low pressure heater and the low pressure cylinder through a pipeline respectively, and the steam inlet is used for mixing the steam exhaust of the medium pressure cylinder and the steam exhaust of the low pressure heater and then conveying the mixed low-quality steam to the heaters; the pipeline connecting the suction port of the jet pump with the pipeline between each low-pressure heater and the low-pressure cylinder is respectively provided with a second isolation valve, the pipeline between the steam inlet of the jet pump and the steam exhaust pipeline of the medium-pressure cylinder is provided with a third isolation valve, and the pipeline between the jet port of the jet pump and the heater is provided with a fourth isolation valve;
the heater is respectively connected with the jet orifice of each jet pump, the heat supply network heater and the heat supply network backwater pipeline through pipelines, the heat supply network backwater is conveyed to the heater through the heat supply network backwater pipeline, then the heater heats low-quality steam input by the jet pump, and then the heated heat supply network backwater is conveyed to the heat supply network heater; in winter, the heat supply network heater does not work to directly supply water to the heat supply network;
when the low-quality steam heating system works, the first isolation valve is closed, and the second isolation valve, the third isolation valve and the fourth isolation valve are opened.
2. The low-quality steam heating system for a wet cooling unit according to claim 1, wherein a fifth isolation valve is arranged on a pipeline between the heating network heater and the medium pressure cylinder steam exhaust pipeline.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810262327.4A CN108488872B (en) | 2018-03-28 | 2018-03-28 | Low-quality steam heating system applied to wet cooling unit |
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| CN201810262327.4A CN108488872B (en) | 2018-03-28 | 2018-03-28 | Low-quality steam heating system applied to wet cooling unit |
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| CN108488872B true CN108488872B (en) | 2024-03-01 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU800396A1 (en) * | 1979-01-29 | 1981-01-30 | Всесоюзный Дважды Ордена Трудовогокрасного Знамени Теплотехническийнаучно-Исследовательский Институтим.Ф.Э.Дзержинского | Thermal power plant |
| CN205477782U (en) * | 2016-03-16 | 2016-08-17 | 华北电力大学 | Utilize ejector to adjust power generation system of little steam turbine of air supply drive water -feeding pump |
| CN206683026U (en) * | 2017-03-21 | 2017-11-28 | 华北电力大学 | A kind of heat supply network multi-heat source co-generation unit based on level-density parameter |
| CN206831646U (en) * | 2017-06-19 | 2018-01-02 | 北京北方三合能源技术有限公司 | A kind of fired power generating unit is exhaust heat stepped to utilize heating system |
| CN208222620U (en) * | 2018-03-28 | 2018-12-11 | 程琛 | A kind of low-quality steam heating system applied to wet type cooling unit |
-
2018
- 2018-03-28 CN CN201810262327.4A patent/CN108488872B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU800396A1 (en) * | 1979-01-29 | 1981-01-30 | Всесоюзный Дважды Ордена Трудовогокрасного Знамени Теплотехническийнаучно-Исследовательский Институтим.Ф.Э.Дзержинского | Thermal power plant |
| CN205477782U (en) * | 2016-03-16 | 2016-08-17 | 华北电力大学 | Utilize ejector to adjust power generation system of little steam turbine of air supply drive water -feeding pump |
| CN206683026U (en) * | 2017-03-21 | 2017-11-28 | 华北电力大学 | A kind of heat supply network multi-heat source co-generation unit based on level-density parameter |
| CN206831646U (en) * | 2017-06-19 | 2018-01-02 | 北京北方三合能源技术有限公司 | A kind of fired power generating unit is exhaust heat stepped to utilize heating system |
| CN208222620U (en) * | 2018-03-28 | 2018-12-11 | 程琛 | A kind of low-quality steam heating system applied to wet type cooling unit |
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| CN108488872A (en) | 2018-09-04 |
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